Typical snowplow control systems include a controller device within the cab of a vehicle, a wiring harness connecting the controller to the vehicle's electrical system and a plug plus one or more harnesses to connect the vehicle to a snowplow. The plug between the vehicle and snowplow harnesses is susceptible to weather and environmental conditions (e.g., snow, water, road salt) and is a common failure point in snowplow control systems. Replacing the wired controller with a wireless controller would eliminate this failure point. Additionally, by replacing the wired controller with a wireless controller, the wiring harness between the vehicle and plow may be eliminated, as the wiring between the vehicle and the plow may be reduced to only a power cable and a ground cable, as control signals from the controller are transmitted wirelessly. The use of a wireless controller would also allow the users increased flexibility in controlling the snowplow. For example, with a wireless controller, snowplow users may have the option of controlling the snowplow remotely while avoiding a common source of control system failure.
Wireless controllers, however, introduce their own set of issues, especially with respect to user safety. Because wireless controllers are free to operate outside the vehicle cab, the controllers may be especially prone to unintended use.
Wireless controllers may also be prone to accidental activation if a user does not realize that the controller is configured to operate the snowplow wirelessly. In this scenario, even a well-intentioned user may accidentally actuate the snowplow if he manipulates the controller within its wireless activation range.
Wireless controllers are also more susceptible to power management issues than wired controllers. More specifically, wireless controllers generally rely on internal batteries for power. Because of this, wireless controllers typically can only remain powered for a limited time before their batteries run out of energy. If a controller battery dies while a user is operating the snowplow, this may also lead to safety hazards, as it may not be possible to change the position of the snowplow (such as from a position that obscures the driver's view or from a position in contact with a road surface), as the controller will not function with a dead battery. In contrast, wired controllers often can draw power from and/or recharge themselves when plugged into another device, such as, for example, a snowplow or vehicle.
Without a proper safety system in place, wireless snowplow controllers may cause a number of safety hazards that may outweigh their benefits and limit their usefulness. While systems for limiting the range of wireless controllers have been implemented, they are flawed. For example, U.S. Pat. No. 6,112,139 to Schubert et al. describes a method to limit the spatial operating range of a wireless controller by configuring receiver circuitry, this method is flawed as, among other things, it still allows more than one controller within the operating range of the receiver to potentially control the snowplow.